A weblog for professionals in electrical, electronic, mechanical and software engineering with content provided by the members of the Long Island Consultant's Network.

July 2009

July 29, 2009

There are lots of tide gages on the Gulf Coast and around Florida keeping track of the rising sea level and the sinking land. The Proudman Oceanographic Laboratory in Liverpool, UK hosts the Permanent Service for Mean Sea Level. Its records for some stations are fairly current, but in the upper end of the Caribbean Sea, where I need to examine the relation between the length of the Loop Current and the hydraulic head driving it, we have a problem. The most recent data is from 1996, supplied by the Mosquito Research and Control Unit on Grand Cayman Island. Data is even more ancient for possible alternative locations on Cuba and Belize.

I was lucky to find some overlap between the beginning of the Gulf of Mexico radar altimetry data starting in 1993 and the Grand Cayman sea level data ending in 1996. Actually, 1994 Grand Cayman sea level data is missing, so there are only three years to compare. It bothers me to think that I came that close to not having this opportunity to test my hypothesis. But who would have thought there was a relationship between the wind-driven pile-up of water at the entrance to the Gulf and the length of the Loop Current?

Now I have to convince others of the need for Grand Cayman sea level data and find some agency that can make it happen. Might need some help with this. Heard Bill Gates was interested in fighting hurricanes. I wonder.........

July 28, 2009

We used to have Monarchs, Red Admirals, Tiger Swallowtails, Spicebush Swallowtails, and other varieties visiting our poor excuse for a garden in South Hempstead. Last year there was some action, but so far this year only a few Cabbage Whites have shown up. The last Spicebush Swallowtail I saw was a few years ago. It was expiring when I found it lying on the ground. It's in a plastic box. I just looked at it. Lifeless.

Not many other insects, either. I had a neighbor who used to sneak herbicide on my lawn to kill the clover because his daughter was allergic to bee stings. No problem now. Lots of clover blossoms, but no pollinators. Not many yellowjackets, either.

Is this happening in other places? I notice a lot of pesticides and herbicides in Home Depot, and a lot of professional landscapers keeping everything well-kept. Have we managed to kill everything except grass and desired plants?

July 23, 2009

The Loop Current (LC) runs through the Gulf of Mexico (GoM) and collects a 200-m-deep pool of hurricane-energizing warm water inside the loop. The hairpin-shaped loop path starts at the Yucatan Channel, heads for New Orleans, turns west, makes a right-hand U-turn west of New Orleans, doubles back, turns left into the Florida Straits, and exits into the Florida Current path leading to the Atlantic Ocean. Most often, the loop does not intrude so far, and sometimes the current goes directly from Yucatan Channel into the Straits.

My hypothesis is that the GoM drains by gravity into the Atlantic and the wind-driven current from the Caribbean supplies more hydraulic head than what is required to overcome turbulent friction in the Straits and Florida Current channel. The LC digs a descending path through the GoM to dissipate the extra power. If this is so, large LC intrusion should occur when the sea level is highest at the GoM entrance.

Grand Cayman Island seems like an ideal location to measure sea level at the inlet of the Yucatan Channel and there are sea level measurements starting in 1976. 1996 is the last year of data. Radar altimetry plots showing the LC path are available from 1993 to present. In the few years of overlap, the sea level rises and then the LC reaches its maximum intrusion. When the sea level drops, the LC shortens by pinching off a ring. This seems to support the hypothesis, but we really need a long, continuous run of sea level data to compare with the radar altimetry.

July 22, 2009

About 6 months ago Dick LaRosa sent me a copy of an article promoting the idea of using hydraulic technology for a certain class of hybrid vehicle. This idea has continued to evolve to a point now it can be seen where it can fit.

The reason for the title "A HYBRID-HYBRID?" was that the hydraulics are in addition perhaps to Parallel or Series Hybrid and intended to fill a perceived gap in BER (Brake Energy Recovery) operation.

A recent article articulates the thought that current hybrids have poor BER at speeds less 6-8mph, and many simply revert to friction brakes at those low speeds. This specific article is more concerned with HEAVY vehicles, such as garbage trucks that are heavy (typically 10-40 tons) and spend a LOT of time in the 0 to 6-8mph, range, (up to 1000 stop-start cycles per day). Example: A 50,000 lb. vehicle @ 8 mph has kinetic energy of 107,555 ft-bs. For 1000 stop-starts per day, this vehicle consumes 3.2 gallon of diesel fuel in acceleration and the brakes dissipate this amount of energy in heat/wear.

What really comes out of this is dividing hybrid BER operations into two ranges i.e. (0-8mph) and (8-80mph or higher). The (0-8mph) range is about 10 sec, and is higher in torque levels; the (8-80mph) is upwards to a few minutes and more modest in torque level.

July 19, 2009

Rob Weiner passed along a Slashdot item about a floating tub whose gunwales are slightly higher than the average ocean surface. Waves splash over the sides so that the average surface inside the tub is higher than the average surface outside the tub. The extra height is supposed to push warm surface water down a long pipe set into the tub's floor. The pipe is supposed to discharge to the cold water layer below the thermocline. What I think will happen is the warm water will enter the pipe until th taller column of warm water balances the shorter column of cooler water outside the pipe. Then the flow stops.

The hurricane danger to the Gulf Coast is not from the shallow layer of solar-heated surface water. It is from the warm water that is swept from the Loop Current by the Coriolis force. The resulting 200-m-deep pool of warm water fills the entire inside of the loop and supplies energy to hurricanes that pass through it. The Loop Current transports from 25 to 30 million cubic meters per second of mostly warm water around the loop. The Coriolis force readily replaces any warm water that sinks into the cooler water below the pool, so the surface stays warm.

July 17, 2009

Go to www.atmocean.com to see some interesting videos about their wave-powered upwelling pumps, which they have been developing for some time. Their program has grown since I first described their work in our newsletter. Their CEO, Philip W. Kithil had expressed some concern about bringing up high concentrations of CO2 and outgassing it to the atmosphere when they bring up nutrient-rich water from below the thermocline. I have suggested to them that the greenhouse effect of the outgassed CO2 can be offset by solar reflectors and evaporators floating on the ocean and shading the water beneath them.

The ocean surface is cooled during winter so it is easily stirred by wind. Nitrates and phosphates are brought to the sunlit layer for photosynthesis. After the Spring phytoplankton bloom, the nutrients are used up and solar heating stratifies the upper ocean, preventing the replacement of nutrients from the cold water below. That's why we need the wave-powered upwelling pumps.

July 14, 2009

For those companies or individuals who wish to file patent applications in the United States, the U.S. patent laws provide a grace period of one year to file the application from the time of an actual sale of, or offer to sell, the invention, or from a public disclosure of the invention, such as at a trade show or in a printed publication. Oftentimes, a company will think of sales and trade shows first, and patenting later, but usually it will shortly thereafter engage the services of a patent attorney, who will prepare and file a patent application in the United States before the one year bar date. However, in such a situation, the company may have inadvertently jeopardized its right to file foreign patent applications.

Excluding the United States, most countries of the world have an “absolute novelty” requirement. That is, if the invention is publicly disclosed anywhere in the world, then this constitutes a bar to filing a patent application in most foreign countries. “Anywhere” should be emphasized here; even if the disclosure occurs in the United States (irrespective of the grace period), it will constitute a bar in Europe and many other countries.

Therefore, before publicly disclosing an invention, decide whether you will seek patent protection and where. If foreign rights are sought, then a patent application should be filed in the United States before the invention is publicly disclosed. By treaty, the U.S. application may then be used as a basis for filing in most foreign countries within one year from the U.S. filing date. The foreign applications will then be effectively accorded the same filing date as the U.S. application, despite any public disclosure of the invention occurring after the U.S. application is filed but before the foreign applications are filed.

The Rule: If you want foreign patent protection for the invention, then file a patent application in the U.S. before you publicly disclose the invention.

If you only want patent protection in the U.S., then you have one year to file a U.S. patent application from the earliest date that you offered the invention for sale, or sold it, or publicly disclosed the invention.

July 11, 2009

A few years ago I had the pleasure of working with a remarkably brilliant engineer – a fellow who could rise to any challenge and get a design working quickly, and quite reliably, out of the box. My impression of this fellow changed when I had the “pleasure” of trying to debug one of his designs. Fred (not his real name) approached things in an incredibly convoluted way; I think that if his left ear itched, he’d reach over the top of his head with his right hand to scratch it. But because he was as talented as he was, he was able to consistently get these designs running. I wasn’t sure whether to respect him less, for the strange approaches, or more, for the fact that he was able to get them to work. Were Fred to be hit by the 8:15 into Grand Central Station, his employer would be in real trouble – not many people would be able to take over his work.

The interesting thing, though, is that we can do this to ourselves. I think we’ll all agree that debugging a design is more challenging than doing the design in the first place. So whatever your level of talent, its possible for you to design something that’s too complex for you to debug.

Read that last sentence again. Basically, we’re all equipped to hang ourselves, if we so choose – consciously, or not. During the design process, we need to be constantly asking ourselves questions like “How will I verify this assumption?” Or, “How can I knowwhat’s going on inside this black box?” Or “If this fails in the field, how can I troubleshoot, short of a visit?” Or, perhaps most importantly “Is there a simpler way to do this?” I’m sure you can think up some more questions of your own that will throttle your cleverness. Bottom line – if we design at the cutting edge of our talents and abilities, we’ll be debugging beyond them.

Abraham Lincoln once said “If I had eight hours to chop down a tree, I'd spend six hours sharpening my ax.” Some of our most important axes are the strategies and architectures we bring to a design. Time spent honing them to match the task at hand will always be time well spent.

July 07, 2009

The July IEEE Spectrum has an article on the shortcomings of the German wind-power industry. This might require increased use of coal, with sequestration of CO2 in geologic formations to reduce the greenhouse effect. A German citizen who was interviewed for the article pointed out the hazard of heavier-than-air CO2 leaking out of the sequestration formation and asphyxiating people and animals in low-lying areas. I remember Carl Schwab describing (in a LICN Newsletter article) mass asphyxiations from naturally-occurring sources of CO2.

This would be something to keep in mind when we consider geologic sequestration as a part of our U.S. "clean" coal technology, which also includes blasting mountain tops into our streams.